Addressing the Munich Security Conference in February, Ukrainian President Petro Poroshenko warned of a growing “hybrid war” waged by Russia “on different battlefields and at different speeds.” Days later, Russian President Vladimir Putin unveiled new missile defense technology that Moscow claims is invincible. Both Poroshenko and Putin are prone to exaggeration, but neither was pulling things out of thin air.

Hypersonic missiles, which can travel at speeds up to 20 times the speed of sound, are emerging among the future cornerstones of new offensive systems that are pitting the world’s powers in a struggle for new technology and the systems to defend against them. While the U.S., China and Russia are rapidly developing the capability to strike at hypersonic speeds, their ability to attack is only as good as their defense against hypersonics.

Time to target is the biggest advantage for hypersonic missiles.

Douglas Barrie, International Institute for Strategic Studies

These missiles hold the potential to alter the global military balance by giving world powers a new precision tool in their arsenal. These missiles, capable of speeds of up to Mach 20 (4 miles a second), could reduce the advantage of proximity to targets that the U.S. has held in much of the world through the unmatched spread of its fleets and bases. They are as fast as ballistic missiles, as maneuverable as cruise missiles, and they are capable of carrying a nuclear or conventional payload. Experts caution that hypersonics are particularly threatening because defense systems built aroundstandard ballistic missiles won’t work against these superfast projectiles. As in the Wild West, the winner will be the quickest draw.

“Time to target is the biggest advantage for hypersonic missiles,” says Douglas Barrie, senior fellow for military aerospace with the International Institute for Strategic Studies, adding that missiles moving faster than at Mach 5 are hard to intercept with most current defense systems. “Current ballistic defense systems don’t look for missiles like these.”

Hypersonic missiles fall into two distinct categories: hypersonic glide vehicles and hypersonic cruise missiles. Hypersonic glide vehicles are launched like traditional intercontinental ballistic missiles, shooting first into space, then re-entering the atmosphere nearer to their targets. At this point a specialized glider deploys, allowing the missile to reach hypersonic speeds. The unpowered glider uses the kinetic force of the re-entry to maneuver the warhead to its target.

Hypersonic cruise missiles, on the other hand, are fired through the atmosphere with a rocket booster. As the missile approaches Mach 5, the booster falls away and a hypersonic scramjet engine propels the missile to its maximum velocity. Hypersonic cruise missiles can be launched off mobile platforms like naval vessels, adding greater versatility to their profile.

Unsurprisingly, defense against these missiles is a key area of focus for nations. While Putin lauded Russia’s new system during his annual March address to the nation, the U.S. Department of Defense is currently reviewing its ballistic missile posture. This includes defensive and offensive capabilities, both of which are lacking in the face of hypersonic weapons.

Though hypersonics have yet to be fielded, defensive capabilities are even further behind.The Cold War brought about the proliferation of ICBMs, bringing global targets within striking distance of the U.S. and the Soviet Union. Along with the development of ICBM systems, anti-ballistic missile systems were developed to neutralize the incoming threats. “The arms race had always been between missile defense and the ability to breach missile defense,” says Xander Snyder, global intelligence analyst with political analyses firm Geopolitical Futures. America’s current missile defense systems were developed in the 1990s, and despite repeated upgrades, have in recent years proved to be less than perfect. In tests since 1999, America’s ABM systems have been successful only 10 times out of 18. Against hypersonic missiles, they wouldn’t stand a chance.

Hypersonic missiles could add to the unpredictability of how wars will play out, suggest experts. The fact that hypersonic glide vehicle missiles are launched like ICMBs, for instance, only adds to the risk of a miscalculation by the target nation or group, suggests Barrie. “There is a risk that the target will defer to the worst-case scenario, irrespective of the payload,” he says, articulating worries that the target may conclude they are under a nuclear attack — even if they are not — and respond accordingly.

From the attacker’s perspective, though, these missiles create doubt for the defender. “Part of the reason for wanting hypersonic technology is creating more questions in the mind of the defender,” says Barrie. “They think, ‘I have hypersonic missiles, supersonic missiles and subsonic ICMBs.’ The defender knows these are three distinct sets of challenges to guard against.”

These missiles may also help reduce destruction during war, suggests Snyder, by taking out an enemy’s ability to wage conventional warfare. “We wouldn’t need to destroy an entire city to stop a country from being able to wage war,” he says. Essentially, critical infrastructure could be neutralized with non-nuclear weaponry. This would force an opponent to the negotiating table without large-scale destruction. As weapons systems become more precise, the cost to infrastructure and human life is reduced.

Hypersonic missiles aren’t distant science fiction, and the stakes are only getting higher as countries develop these weapons and corresponding defense systems. To experts, the development of hypersonic missile technology isn’t an arms race, but an inevitable evolution of current capabilities. The world’s major powers, says Barrie, may boast these weapons in their inventories within a decade. The big question? Who gets there first.